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Upgrading from 20 gallon to 75 gallon

Hi everybody! I've had a 20 gallon high tank for several years with a Fluval/Aquaclear 20 gallon HOB filter and a Fluval/Aquaclear 30 gallon HOB filter. There's CaribSea sand substrate, fake plants and fake logs and caves. For fish I have 4 harlequin rasboras, 3 spotted cory's (Corydoras ambiacus), 2 otto's, and a single electric blue dwarf ram cichlid (who killed his friend but mostly leaves the other fish alone).

I have a new empty 75 gallon tank, 48 inches across, 18 inches back, and 20 inches high. I got a 48 inch Marineland aquarium plant led light with timer (and an extra Marineland single bright led 36 inches I can add if necessary). I also have a fluvial 306 canister filter which I know is only rated for 70 gallons but I'll add one of the HOB filters from the 20 gallon to get the nitrogen cycle started. I haven't put anything in the tank yet.

I want to have a good number of plants and some driftwood in the tank but I've never had plants before and I have a limited budget (also I'm not good at DIY) so I'm planning on getting pool filter sand and then supplementing with root tabs, I don't want to mess with CO2.

Ideally I would take all my fish from the 20 gallon and put them in the 75 with some fish that would get along with them, I'd like as many varieties as possible but very peaceful, I hate to see fish fight. What are some good plants for me to start with and some interesting fish. I was thinking maybe I would eventually get discus but they seem pretty high maintenance and I heard angels can get aggressive, so maybe Bozemani rainbows, or rose line sharks, or rummy nose tetras, black neons, maybe whiptail catfish? Is there another centerpiece fish that would get along with my dwarf ram like a Bolivian ram or should I leave him and some of the others in the 20 gallon, I would like maximum flexibility but definitely want some cory's and some schooling fish. Thanks in advance for your thoughts!

looks like you've got a pretty good list of possibilities. Roselines are gorgeous fish - expensive but gorgeous :o) Rainbows would be great in a 75. Congo tetras are gorgeous fish too and would be okay in there. Or you could go all tetra and get 3 nice big schools of rummies, congos and another tetra you find appealing. I'm sure others will chime in with ideas.
Also looks like you've got a smooth transition plan. Just watch your water parameters closely for a while as you may have a mini cycle as new BB grows to accommodate your fish.
I'd leave the ram in the 20 since he's already killed another ram.
Plants: Hornwort is inexpensive and grows quickly. You can plant some in the substrate and let some float if you like. Amazon swords grow nicely as do java ferns - and the good news about the java ferns is they produce lots of little plantlets from their leaves that you can transplant. Hygro is also a great plant and can spread like wildfire.

You could up your school of harleys and cories and the 20 would be nicely filled. Cories are more comfortable and active in groups of at least 6 of their own kind. same with the ottos. add some mystery snails and it would look great.

Originally Posted by Somethingfishy101

Thanks for the advice! What else do you think might go nicely with the ram in the 20?

I wouldn't mess with a large school of a slightly larger tetra. I would stick with 2 large smaller schools, but stable school of 6-8 larger schoolers(Diamonds, Congos, or Boesemanis), OR you could get a group of 5 small angels and remove the other 3 until a pair forms. This is a 75 gallon tank here, and that's 4 feet of swimming room here, any more than 10 of a large schooler would make it very difficult for the smaller schooling fish to thrive in a tank this size.

You have room for some kind of fish at the top, such as a pair of Mollies, Swordtails, or even Killifish. I would only get a few hardy fish at the top of this tank rather than another school of small schoolers, just because you're going to have so much action in the middle and mid-top of the tank.

If you go with the school of 6-8, you have the room for a gourami, and if you go with the angels, they are already your centerpiece fish, because they reach up to 6 inches, sometimes a bit more.

You could probably fit in a small pleco at the bottom of your tank, like a bristlenose, or you could go fancy and get a type of hypancistrus pleco, which are mainly carnivorous and won't really touch your plants. Just make sure whatever pleco you get, you have a decent cave just for it, as well as a shady area for your cories because sometimes they want shade. Some hypancistrus get very pricy, but in return are some of the most stunning fish in the hobby. Just google "hypancistrus pleco" and you'll see what I'm talking about.

I used to have a planted Discus tank years ago and had no problem. Also I have seen many videos of Discus in planted tanks. I maybe mistaken on the Ottos part, but I thought people complain that ottos suck on the leaves. Sorry if I am wrong.